Variation in Scolex Morphology within and between Some Species of the Genus Proteocephalus Weinland (Cestoda, Proteocephala) with References to Strobilar Morphology

The scolex morphology of some Proteocephalus species from fish caught in fresh and brackish waters in Norway, as revealed by scanning and transmission electron microscopy and light microscopy, is described. The size and form of the fifth apical sucker proved to be a very pure character for identification. In spite of this, however, the scoleces of different species revealed specific characters which together with strobilar characters should be well suited for species discrimination and identification.